[norcal_68]

Can you guys help me decode this 12 Bolt out of my 69? It came with the car, 3.73 non-posi. I'm only able to pull axle stamp numbers.

The casting numbers are almost unreadable, there is so much paint caked over it. I will have to scrub them.

Also, I was unable to locate casting #'s, I looked on CRG, is the number on top or bottom of the area that they've called out? I don't see the numbers anywhere near. It's a tight squeeze under there!

The axle stamp looks like 0 ?Z 05120 E

Also, the rear end has traction bars, is this original to the axel?

Thanks.

[HwyStarJoe]

It's not a 1st Gen rear end.
The slapper bars weren't installed on 1st Gens. Those are aftermarket.
Neither was that sway bar.
Wish the numbers were easier to see.

[norcal_68]

Thanks. Can I just unbolt them as they are? There may be a spot weld on them but I didn't want to just start unbolting stuff without asking first.

[TJS69]

Joe, Both the slapper bars and the sway bar are added to a first gen. axle.

C QZ 0512G
.........E

A QZ code in '69 was for a 4.56 12 Bolt. (If that is a Q)

late 69 axles may be stamped with the 1970 style C prefix (e.g. CBT instead of just BT)

The E - stands for an Eaton Posi.

I don't think it IS what it WAS.

[norcal_68]

I hope so, immstarting to think I bought a Chevelle. My 396 is from a Chevelle and I think 66 12 bolts will work for 1st gen F bodies.

[HwyStarJoe]

Originally Posted by TJS69

Joe, Both the slapper bars and the sway bar are added to a first gen. axle.

What do mean? As usual, I probably wasn't clear in how I worded my reply.

[TJS69]

Originally Posted by HwyStarJoe

It's not a 1st Gen rear end.
The slapper bars weren't installed on 1st Gens. Those are aftermarket.
Neither was that sway bar.
Wish the numbers were easier to see.

You are correct in saying those were not installed by the factory on a first generation Camaro. That doesn't mean that someone else didn't add those to a first generation Camaro. The rear could still be factory stock rear in a first gen !

[TJS69]

Originally Posted by norcal_68

I hope so, immstarting to think I bought a Chevelle. My 396 is from a Chevelle and I think 66 12 bolts will work for 1st gen F bodies.

Nothing on the rear points to a '66 Chevelle. At least I don't think it does.

The 3 letter code points to a late '69 Camaro rear.

C QZ = 4.56 gearing; 0512 = May 12; G = Detroit Gear & Axle plant

E = Eaton Posi

The posi carrier and gears could have easily been changed to more "street friendly" 3.73 gears. They would of had to change the carrier to swap to a different series of gears. I don't think 3.73's were available in a 4 series in the early 1970's.

The only thing that confuses me is that it supposedly came with 4 wheel Disc brakes !

[Eric Kammerer]

Doesn't it appear to have aftermarket/Ford/Mopar weld on perches, vs the cradle type OE?

[norcal_68]

I say Chevelle because I saw that they have the 'E' on the second line, but I think I just saw that elsewhere on a Camaro axel. CRG wasn't that clear.

When we swapped the 3.73s for 3.42's, there was no posi-unit. It's was apparent someone had been in there before.


Is the Ø meant to be a Q? It doesn't look like a Q. Imo.

On NastyZ28.com there is an axel that has C ØX 0506G1 E code. The ØX looks alot like the ØZ on mine. Thoughts?


http://www.nastyz28.com/forum/showthread.php?t=146688

Originally Posted by TJS69

Nothing on the rear points to a '66 Chevelle. At least I don't think it does.

The 3 letter code points to a late '69 Camaro rear.

C QZ = 4.56 gearing; 0512 = May 12; G = Detroit Gear & Axle plant

E = Eaton Posi

The posi carrier and gears could have easily been changed to more "street friendly" 3.73 gears. They would of had to change the carrier to swap to a different series of gears. I don't think 3.73's were available in a 4 series in the early 1970's.

The only thing that confuses me is that it supposedly came with 4 wheel Disc brakes !

[TJS69]

You are correct, it does look more like the one on Nastyz28. I'll do some more digging.

[norcal_68]

Awesome. thanks! I'll try and get the casting numbers tonight.

Originally Posted by TJS69

You are correct, it does look more like the one on Nastyz28. I'll do some more digging.

[norcal_68]

Looks like C0Z is a 70' axle code. Is it possible it's a 70? Though, they're an inch wider.

http://www.nastyz28.com/camaro/camaro70.php

[bcm66]

COZ is a 1970 Camaro code.

Assembly date on there of May 12 points to it being a 70, but get the casting number and casting date off the center section. Might need some paint remover. In 1970, in a Camaro rear axle coded COZ is for 3.73 locking (posi).

Posi may have given out and someone stuck an open carrier in there. What are the numbers on the ring gear? If you have the cover off.

[big gear head]

It's probably a '70 because the original spring perches have been cut off and after market perches have been welded on. The '70 rear end is 1/2 inch wider on each side for a total of 1 inch. The spring perches are also about 2 1/4 inches farther apart, which would explain why the after market perches were used.